1. Field of the Invention
The present invention is with respect to a flexible armored synthetic resin hose, more specifically for showers, with an extruded inner hose part of thermoplastic or elastomeric material, an extruded outer hose part of thermoplastic or elastomeric material, which is at least partly supported so as to be spaced from the inner hose part, and a reinforcement helix for armoring the hose, said helix being placed between said inner and said outer hose parts.
2. Prior Art
In an earlier design of flexible synthetic resin hose (see German Pat. No. 2,261,126) a wire helix of round cross-section and made of metal or a hard synthetic resin is placed round an inner hose part of plasticised polyvinyl chloride ("PVC") without however being joined with the inner hose part. Between the coils of the wire helix a thin hard PVC band is coiled which is markedly broader than the thickness of the wire of the wire helix. This coiled hard PVC band is joined not only with the inner hose part but furthermore with the outer hose part along its full length, it having the purpose of making certain that the inner hose part is not inwardly buckled on bending the hose sharply and for this reason decresing the flow cross-section within the hose. Such a hose is however somewhat stiff because the hard PVC band, which together with the inner hose part and the outer hose part takes the form of a generally thick compound body, may not be readily bent. For this reason, on bending that part, of the outer hose part placed on the wire helix is forced together to a high degree and outwardly buckled on the side of the hose with the smaller radius so that the material is acted upon by high forces.
In a further earlier design of flexible synthetic resin hose (see German Offenlegungsschrift specification No. 2,722,928), a flexible reinforcement band of relatively hard synthetic resin is coiled about the inner hose part and strongly joined with it and with the outer hose part, that is to say with the outer part, by reinforcement lips running outward therefrom in a radial direction and running round the structure, such lips at the same time fixing the spacing between the outer and inner hose parts. In the case of this flexible hose part the space between the coils of the reinforcement helix is free so that the hose has good bending properties. However it has now turned out that the flexibility of the hose might be made even better for general use. Furthermore there have been shortcomings in connection with adhesively joining the hard synthetic resin with the plastizised synthetic resin of the hose parts.